Project Thumper Walkthrough

For those of you that don’t know, The Geek Group is the world’s largest not-for-profit Hackerspace. Lately they have been working on developing better videos for their YouTube channel, and have just released a stunning CGI animation of the build, operation, and explanation of Project Thumper.

So what is Project Thumper? In the simplest terms, it’s a giant capacitor, or more specifically, an entire server rack filled with capacitors. The Hackerspace uses it for experiments and demonstrations — but from the looks of their videos, they mostly just use it to blow things up, as shown in their 2008 Project Promo video. I think we would too. They even used it to blow up an iPhone! (Skip to 3:00 for the explosion). We think someone with a high-speed camera really needs to film Thumper in action!

The awesome CGI animation explanation of it is after the break.

Last year we covered another one of their projects called Project Stomper, a very similar idea, but used to shrink quarters instead.

Maybe it’s just me, but I love the Geek Group too. However, Chris just rubs me the wrong way. I know he means well, but sometimes I feel like his personality is what’s holding me back from engaging more in the group.

Chris is, I guess, the proprietor of the group. I don’t want to input my bias. So, my recommendation is to watch the blogs and video and come to your own conclusions. Like I said, all-in-all, I like what they’re doing. Just, sometimes I wish they had a different person at the helm.

I totally agree with you. I used to actually volunteer at GG here in grand rapids for a while and while i like the concept of what they are trying to do, their attitudes were generally very demeaning to anyone that had any interests, which put a lot of people off from joining.

Really? From what I’ve seen, TGG is a haven, not an exclusive group. I showed up as a loner, and was welcomed into the group. Sadly, online only as of yet. Nobody is demeaning, except in a sarcastic or joking manner, and I haven’t seen anybody rejected for their interests. Chris genuinely just wants to make people happy. If he was snappish, it was probably because of all the stress he’s under. Chris has to /be/ the Geek Group. He has to make management decisions that can either doom the group, or have it succeed. He’s there seven days a week, probably almost 365 days a year. The only day I haven’t seen a blog with him in it, was a day when he was sick and couldn’t get out of bed. Chris has sacrificed his life for TGG. And he deserves respect for it.

That’s hilarious; going to the web site of another person who also rubs others the wrong way to read opinions about someone who rubs others the wrong way. To compare what David Jones does to what the Geek Group does would be comparing Apples To Oranges. The Geek Group operates a physical space where the public can visit David Doesn’t. To operate a physical plant as expansive at he Geek Group is trying to to has to depend on donations, and the staff is always walking a fine line no matter who the organization is. All I’m seeing is that the movers and shakers getting thing done while exposing themselves to criticism get the criticism.

I just think that you don’t have to like Chris to enjoy what TGG has to offer. That animation video remain awesome while you like him or not.
Also perhaps your impression comes from the fact that the blog is mainly run by him, but that’s just because of his desire to show what’s going on. Not every staff member would have the time to do the same (sometimes Batman shoot some blog though) and is not that he’s ALWAYS blogging either.
Anyway the point is that TGG is more than just a person and you should evaluate it considering that.

It was awesome to wake up and see this here, on one of my most favorite sites of the internet. It is one of the best videos that The Geek Group has ever released. The A/V department has taken it completely to the next level.

Dave, and anyone that may feel that way: Please don’t forget about the many other awesome people in that building. I came to TGG from Colorado, and I came for the cause, and to build a world wide community where everyone can work together for the greater good. Everyone here works very hard to make this possible, and loves it. We work just as hard to be here to help you learn, because we’re The Geek Group. Singling out one person, and not giving the rest of the group a chance would not be fair. Reminds me of grade school when I was singled out and not given a chance just because I was different, why perpetuate a stereotype that most geeks wish they could escape?

If you cannot accept that people are different, have different personalities, how do you expect to evolve in the modern age?

I am on the Livestream much of the day. Everyone from 12 years old to 40 fixes cars with me, brainstorms ideas, and has a blast building everything from phase change refrigeration computer cases to video systems and beyond. If you keep from poking in on the live stream and IRC for the sole reason that you don’t like somebody who shows their face for 1/16th of the entire day, you’re missing out on so much fun!

I am not here for Chris, I didn’t drive 1100 miles with an empty bank account to see Chris. I am here for you, for The Geek Group. If your personality clashes with him, don’t engage with him, but 15/16ths of the rest of the day I encourage you to stop in and say hi. I am always open for a great conversation and new ideas.

Bravo to Steven, Elizabeth, Moose, Mike, Aaron, Rocco, and Brian. It was all of you in your day to day struggle that made this real. I couldn’t feel more at home.

They should measure what the voltage is left after the fire, as then they can figure out how many joules was actually used. This would give a more realistic number of how many watts are being discharged over the firing time. Electrolytic caps don’t do near as well compared to Pluse caps designed for this application. I get the impression that they could have gotten the same results using a few large HV Pulse caps from ebay and also save some space and the work time needed to build that rack of electrolytic caps.

IIRC these caps were actually donated by the manufacturer. HV pulse caps of the size required would have had killer shipping costs, and would have many holes blown through them by now .Most of the pulse caps go for tesla coils, where rapid recharge and repeated firing is necessary. Thumper can only really fire once every two minutes or so.

Hiya Everybody, I’m one of the guys that put Thumper together and I’ve been asked to stop by to field some questions.

First off, someone asked about the wattage and current values we’re quoting. Well, Watts = Volts times Amps. Thumper’s capacitor bank is comprised of 40 strings of four DCM202T450DF2B capacitors in series. Each cap is rated at 450V. With four in series our bank is rated at 1800VDC and that’s what we charge the bank to (not 1600V) So there’s our first number.

Quite some time ago we had a member come in with a DSO. (I think his name was Sean) He connected it across part of the copper bus and measured the peak voltage and duration of the pulse across that section of bus. He calculated the resistance of copper he was across and used it to calculate the systems peak current (Ap=Vp/R) So that gave us a peak value of 80000 Amps, Our second number.

Watts = Volts * Amps, so 1800V * 80000A = 144,000,000 Watts.

Watts are a measurement of power, Joules are a measurement of power over time, or energy. Thumper’s impulse lasts for a very short amount of time. The graph is almost straight up and down. The .003 seconds mentioned is not the duration of time that the 144MW lasts, It’s the time it takes the current to surge to a peak and fall back to zero.

Someone asked what the voltage on the bank is after firing… That depends a lot on what we’re using as a “fuse”. There’s a little bit of stray inductance in the system. (ESL in the caps and parasitic inductance from the bus wiring) So when Thumper fires there’s a bit of resonant ringing. For a particularly good firing it’s not uncommon for the bank to be left with a negative voltage.

There was also a mention of using pulse capacitors. We have another impulse generator named Stomper that uses three of those. Here’s Stomper’s walkthrough: http://www.youtube.co

Hiya Everybody, I’m one of the guys that put Thumper together and I’ve been asked to stop by.

First off, someone asked about the wattage and current values we’re quoting. Well, Watts = Volts times Amps. Thumper’s capacitor bank is comprised of 40 strings of four DCM202T450DF2B capacitors in series. Each cap is rated at 450V. With four in series our bank is rated at 1800VDC and that’s what we charge the bank to (not 1600V) So there’s our first number.

Quite some time ago we had a member come in with a DSO. (I think his name was Sean) He connected it across part of the copper bus and measured the peak voltage and duration of the pulse across that section of bus. He calculated the resistance of copper he was across and used it to calculate the systems peak current (Ap=Vp/R) So that gave us 80000 Amps, Our second number.

Watts = Volts * Amps, so 1800V * 80000A = 144,000,000 Watts.

Watts are a measurement of power, Joules are a measurement of power over time, or energy. Thumper’s impulse lasts for a very short amount of time. The graph is almost straight up and down. The .003 seconds mentioned is not the duration of time that the 144MW lasts, It’s the time it takes the current to surge to a peak and fall back to zero.

Someone asked what the voltage on the bank is after firing… That depends a lot on what we’re using as a “fuse”. There’s a little bit of stray inductance in the system. (ESL in the caps and parasitic inductance from the bus wiring) So when Thumper fires there’s a bit of resonant ringing. For a particularly good firing it’s not uncommon for the bank to be left with a negative voltage.

I can understand how Chris winds people up the wrong way he’s big personality and sometimes he comes across as a bit over powering, but I’ve also seen him give people who would normally be a withdraw and lack confidence, that extra confidence they need to do good things.

He’s done a lot of good and sometimes us clever people sometimes need someone with big personality in our groups.